The present application is related to an avalanche diode arrangement and a method for providing a detection signal.
An avalanche diode is a diode that is designed to obtain avalanche breakdown at a reverse bias voltage. An avalanche diode can be used as a single photon avalanche diode or detector, abbreviated as SPAD. A single photon is able to trigger the avalanche breakdown. This mode of operation is named Geiger mode.
A SPAD device has to be operated with a bias voltage several volts above the breakdown voltage of the avalanche diode. Thus, the bias voltage is the sum of the breakdown voltage and of an excess bias voltage. Keeping the excess bias voltage constant ensures that the sensitivity of the SPAD device remains constant as well. The breakdown voltage may vary according to manufacturing conditions and temperature. If a constant bias voltage is applied, the variation of the breakdown voltage would result in a change of the excess bias voltage causing a loss of sensitivity, the damaging of circuits of the avalanche diode arrangement, an increased dark count rate, abbreviated as DCR, or after pulsing probability.